Proper diet improves iron deficiencies

ON CALL

Q: Just after delivery of my second child, my doctor said I had a borderline iron deficiency. What kind of diet would improve my intake of iron?

A: The choice of a diet to prevent or overcome iron deficiency is tricky because it depends both on the amount and form of the iron in your foods as well as other dietary factors.

The two major forms of dietary iron are heme and nonheme iron. Heme iron, which comes from the muscle protein (myoglobin) found in meat, poultry and fish, comprises about half the iron in these animal products and is absorbed much better than nonheme iron. Red meats are especially rich in heme iron. Nonheme iron is poorly absorbed. It makes up the remainder of the iron in animal foods as well as all of the iron in vegetables, fruits, grains and iron-fortified foods. Milk, milk products and fruits are low in iron. The absorption of nonheme iron is greatly enhanced when vegetables or grains are eaten at the same meal with animal foods or those containing vitamin C.

Iron absorption is lowered by oxalic acid (found in spinach and other vegetables), tannins of fruits and vegetables (but not tea), soy products and the food additive EDTA.

Iron absorption is also significantly influenced by your body's need for iron. People with iron deficiency may absorb two to five times more of the iron in their diet, especially the nonheme iron, than people with full stores of body iron.

Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine and associate dean for academic affairs at the school.